The use of lofty, fibrous, nonwoven abrasive products for scouring surfaces such as the soiled surfaces of pots and pans is well known. These products are typically lofty, nonwoven, open mats formed of fibers which are bonded together at points where they intersect and contact each other.
Low-density abrasive products of this type can be formed of randomly disposed staple fibers which are bonded together at points of contact with a binder that contains abrasive particles. The staple fibers typically have been crimped and are laid down by equipment such as a "Rando Webber" web-forming machine (marketed by the Curlator Corporation of Rochester, N.Y. and described in U.S. Pat. Nos. 2,541,915; 2,700,188; 2,703,441 and 2,744,294) to form a lofty open mat. One very successful commercial embodiment of such an abrasive product is that sold under the trade designation "Scotch-Brite" by the 3M Company of St. Paul, Minn. Low-density abrasive products of this type can be prepared by the method disclosed by Hoover et al. in U.S. Pat. No. 2,958,593.
While such abrasive products have had excellent commercial success, their production requires a considerable investment in equipment. A "Rando Webber" web-forming machine, for example, can cost in the thousands of dollars. Additionally, the fibers used to form the web of such abrasive products typically require chopping to produce staple fibers which is both costly and time consuming.
The low density abrasive products described above may also be formed of webs or mats of continuous fibers. For example, in U.S. Pat. No. 4,227,350, Fitzer discloses a low-density abrasive product comprising a uniform cross-section, generally flat-surfaced, open, porous, lofty web of autogenously bonded, continuous, undulated, interengaged filaments. The web of Fitzer is formed by downwardly extruding a plurality of thermoplastic organic filaments into a quench bath. As the filaments enter the quench bath, they begin to coil and undulate, thereby setting up a degree of resistance to the flow of the molten filaments, causing the molten filaments to oscillate just above the bath surface. The spacing of the extrusion openings from which the filaments are formed is such that, as the molten filaments coil and undulate at the bath surface, adjacent filaments touch one another. The coiling and undulating filaments are still sufficiently tacky as this occurs, and, where the filaments touch, most adhere to one another to cause autogenous bonding to produce a lofty, open, porous, handleable filament web. The web, so formed, is then impregnated with a tough binder resin which adherently bonds the filaments of the web together and also bonds a multitude of abrasive granules, uniformly dispersed throughout the web, to the surface of the filaments.
Additionally, fibrous polishing and/or abrading materials can be prepared from continuous or substantially continuous synthetic filaments by the method disclosed by Zimmer et al. in U.S. Pat. No. 3,260,582. In this method crimped or curled continuous filaments are straightened out under tension into a substantially parallel relationship with one another, uniformly coated while under tension, with an adhesive which may or may not contain abrasive particles, interlocked one with another by release of such tension and then set in a permanently interlocked and lofty, open, three-dimensional state by curing or setting up the adhesive.